Tobacco or other herbs are typically smoked by burning and inhaling the combustion fumes and smoke. Smoking implements are generally known. A common smoking implement is referred to as a pipe. In traditional pipes, tobacco or some other smoking substance is burned, producing smoke for human consumption. Benefits of traditional pipes include simplicity of construction and use, compactness for convenient transport, and low cost.
In recent years, interest has grown in the technique of “vaporization” in which the smoking material is carefully heated so that the desired flavor and psychoactive components are liberated, and combustion is minimized. Vaporization provides many benefits over smoking. When performed properly, vaporization does not produce nearly as much toxic and carcinogenic pyrolytic products as smoking. Also, vaporization is smoother and more flavorful, and lacks a burned taste that many find disagreeable. Further, vaporization allows more efficient use of smoking materials, since psychoactive compounds are not destroyed by combustion. Vaporization occurs at the temperature of the boiling point of the desired active component. Most plants and herbs of interest fall into the temperature range of 220-400 degrees Fahrenheit. A major technical challenge for vaporizers is maintaining the desired temperature range.
Most vaporizers in use today are electrically powered, either directly by electrical line power or indirectly by using a temperature-controlled heat gun.
Electrically/battery powered devices are shown in U.S. Pat. No. 6,990,978; U.S. Pat. No. 5,993,748; U.S. Pat. No. 4,141,369; and U.S. Pat. No. 4,303,083. The most advanced of these devices are capable of adjusting heat output to ensure that the smoking material stays within the desired temperature range. The length of time for heat output is easily controlled. Electrical vaporization devices are not portable and require electrical line power. Some electrical vaporizers are now powered by batteries. Current battery life is less than 30 minutes and the vaporizer is inoperable during recharge. Compared to traditional pipes, electrically powered vaporizers are less rugged, harder to manufacture, less compact and portable and require electrical line power supply or batteries.
U.S. Pat. No. 6,717,494 describes a vaporizer attachment for a pipe so that the pipe can be coupled to an electric heat gun. Carrying the vaporizer attachment with a pipe is only slightly less convenient than carrying a pipe alone, but the added requirement of using an electric heat gun makes this invention less convenient than a traditional pipe. The length of time for heat output is easily controlled. Using an electric heat gun also ensures that an adjustable, consistent temperature heat source is provided, however, no means is provided for adjusting for other variables such as the inhale rate of the smoker or improper placement of the heat source.
U.S. Pat. No. 4,219,032 describes a smoking device using a fuel element, and therefore does not require an electrical/battery powered heat source. The preferred embodiment of this patent requires a liquid reservoir and performance of this embodiment is sensitive to the apparatus' orientation angle from the horizontal. Though an electrical heat source (with the attendant advantages and disadvantages) is within the scope of this invention, the heat source in the preferred embodiment comprises burning charcoal which makes it difficult to precisely control the heat source's start and stop. The preferred embodiment of this invention is not provided with means to automatically adjust the temperature of the smoking materials to ensure that the smoking materials are always hot enough to vaporize the desired components but not hot enough for combustion. No means are provided for adjusting for variables such as the temperature of the burning fuel and the inhale rate of the smoker. This invention requires a separate combustion chamber additional to the bowl which holds the smokable material.
PCT/US2002/041771 discloses a device that uses a flame for vaporizing flavor and psychoactive compounds from smoking materials such as tobacco. Because the preferred embodiment uses butane as a fuel source, it has some of the advantages of traditional pipes. Namely, it requires no electrical power line or batteries. It is relatively more complex and is not as compact and portable as a traditional pipe. The device has a filter unit with a porous flame filter. Flame is supplied to the flame filter, and inhalation causes ambient air to enter the flame filter as well. The flame has to be produced and sustained during each inhalation. The flame exhaust and ambient air are mixed within the flame filter and produce an air stream of intermediate temperature that hopefully is hot enough to vaporize desirable components from the smoking material but not hot enough to burn the smoking material. The temperature of the smoking material will vary with the smokers inhale rate and flame temperature and position. An airflow shutter comprising bimetallic strips is disclosed for making automatic adjustments to maintain the desired temperature of the smoking material by restricting the flow of hot air (making the user's inhalation more difficult) into the vaporization chamber. The disclosed airflow shutter configuration does not permit inhale rates that vary independently of hot air temperature. In other embodiments, maintaining the necessary temperature depends on the skill and experience of the smoker. A bimetallic strip to aid the smoker in determining the temperature near the smoking material is disclosed. The invention requires heat and oxidation resistant flame filters that have high thermal conductivity and are porous enough to breathe through. A flame filter must be designed and sized for the vaporizer. Because the flame filter becomes too hot to safely handle, means for safely attaching/mounting the flame filter must also be provided. Some flame filters require protective coatings. The flame filter ultimately adds complexity, expense, and safety issues not found in traditional pipes.
The present inventor is not aware of any prior art vaporization implement that provides a purely mechanical means for automatically regulating the temperature of a smoking material to vaporize the desired ingredients without burning the smoking material regardless of inhale rate, provides for an effortless inhale, requires no battery or electrical power source, is as conveniently portable, rugged, and easy to use as a traditional pipe, and requires no more additional apparatus than a traditional pipe.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.